Dental lift



y 1966 R. R. ROBERTS ETAL 3,252,221

DENTAL LIFT Filed July 18, 1962 Fig. 7

magmas L445 532 A United States Patent 3,252,221 DENTAL LIFT Ralph R. Roberts, Glen Rock, NJ. (48 Winding Way, Upper Saddle River, N.J.), and Donald W. Brooks, 660 Church St., Oradell, NJ.

Filed July 18, 1962, Ser. No. 210,717 2 Claims. (Cl. 32-40) This invention relates to improvements in impression forms and methods of use as applied to dentistry.

In the making of inlays, crowns and the like, the dentist must make an impression of a prepared tooth. To assist in the taking of the impressions, investment forms commonly referred to as copper bands are commonly used. These .copper bands, after being selected for size and trimmed to suit the tooth being fitted, are customarily filled with a wax or composition designed to accept and retain an impression. The tooth having been prepared for an impression, the copper band with the properly softened impression material therein is placed on the tooth and the dentist then finally presses the wax or composition into the prepared tooth. After the im pression has set, the copper band with the formed impression inside is withdrawn or lifted off the tooth. The removal of the impression from the tooth requires exactness and patience on the part of the dentist, for if in removal the copper band is accidentally rocked or caused to be lifted in an indirect manner, the impression is distorted and the resulting inlay, usually of precious metal, does not fit properly. The mis-matching of the inlay usually requires the dentist to again repeat the process of taking an impression and making a new inlay.

It is an object of this invention to provide apparatus and means for easily executing a straight lift of the copper band and the impression.

It is a further intent of this invention to provide investment forms with bail attaching means and bails adapted to attach to the investment forms.

Another object of this invention is to provide fulcrum means adapted to engage the bail of the tubular investment forms.

Further objects and advantages characteristic of the invention, both in its novel features of construction and also its operation and arrangement of parts, will become apparent in the following specification as illustrated in the accompanying drawing wherein:

FIG. 1 is a side view of the invention as used;

FIG. 2 is a side view of a copper band with bail holes;

FIG. 3 is a sectional view taken on the line 33 of FIG. 2;

FIG. 4 is a side view of an alternate embodiment of a copper band;

FIG. 5 is a side view of a bail with inwardly formed hook ends;

FIG. 6 is a side view of a bail with outwardly formed hook ends;

FIG. 7 is a top view of another embodiment of a bail form;

FIG. 8 is a side view of the elements used in the fulcrum lift;

FIG. 9 is a top view of the elements shown in FIG. 8.

Referring now more particularly to the drawing, a tooth 15, as prepared for taking an impression, is shown in FIG. 1. An investment form 16, is shown on the tooth 15. This form 16 in the present instance is of tubular shape and is shown in phantom outline at position A. After removal from tooth 15, the investment form 16 is raised to position B. A bail 17, preferably of wire, is attached to the investment form 16, so as to provide a means of lifting the investment form 16 from the tooth 15. In the 3,252,221 Patented May 24, 1966 ice preferred embodiment, passageways 18 are formed in the form 16 and are located adjacent to the upper end of the form 16. These passageways 18 provide a means whereby the bail 17 can be attached to the investment form 16.

To provide a fulcrum lifting means for the investment form 16, a plier like apparatus is used. Included in the preferred essential elements is a top member 19 which is formed with a straight nosed element similar to the formed end of a needle nose plier. Adjacent to the outer end of the nose is a retaining groove means 20 so arranged and constructed as to receive the bail 17. For convenience and ease in grasping and holding, the top member 19 has the opposite end, in the present instance, formed with a curved handle element. Co-acting with and forming the support for the top-member 19 is a bottom member 21 in which one end has a formed right angle projection. The right-angled tip end of the projection is constructed so that the tip normally will rest on an adjacent or near tooth of tooth 15 being treated. Opposite the right-angled tip end of the bottom member 21 is a curved handle shaped similarly to top member 19. The top member 19 and bottom member 21 are held in pivotal relationship by a pivot pin 22. Suitable bearing means 23 I are provided in members 19 and 21 for pin 22. A spring 24 urges the handle portions apart. The dentist in using the fulcrum lift first overcomes the bias of spring 24 then continues the raising of the outer tip of top element 19 to cause the lifting of investment form 16 from the prepared tooth 15 to position B. 1

The investment form 16 shown in FIGS. 2-3 exemplifies the preferred arrangement of the passageways 18 for use with the bail 17. ment form 25 has an outwardly rolled edge 26. The edge 26 is rolled so as to provide a recess adjacent to the wall of the form 25.

A bail 17 as shown in FIG. 5 is bent with the ends curved into internally turned books 27. The hooks 27 are so arranged as to mate with the investment form 16 in such manner that the bail 17 will lie on the outside of the form 16.

An alternate bail 28 shown in FIG. 6 has the ends curved into externally turned hook means 29. The hooks 29 engage the investment form 16, wherein the hooks 29 go through the passageways 18. In this manner of assembly the bail 28 is inside the form 16. In this arrangement the bail 28 tends to stand upright.

A layout of a bail 30 is shown in FIG. 7 and upon which spread ends 31 are constructed. The ba-il 30' is then curved to a U-shape as exemplified in FIG. 4 with ends 31 rolled under so as to engage the recess formed adjacent to the wall of the investment form 25.

FIGS. 8 and 9 show the elements of the fulcrum lift arranged in close proximity. Although the handle forms in the present instance are curved similar to the handles of most plier assemblies, other configurations may be used as suits the user.

Use and operation The dentist after preparing the tooth 15 for the taking of the impression must exercise great care in seeing that the impression is made accurate. An investment form 16 is filled with a material for taking impressions. A bail 17 is hooked on the investment form 16 and the said form is then pushed onto prepared tooth 15 and at position A is allowed to wait until the impression material has set. The dentist now takes the fulcrum lift with the jaws together and inserts the top member 19 into the space between the apex of bail 17 and investment form 16. Then placing the right angled projection of bottom member 21 on a convenient tooth, the handles are grasped and the jaws forced apart until bail 17 engages and is seated in grove means 20. The dentist then con- In FIG. 4, an alternate investtinues to squeeze the handles together until the investment form 16 reaches position B. In this manner the dentist is able to pull the investment form 16 with the impression from the tooth 15 in a straight even pull.

If investment form 25 is used in making the impression the impression material is placed in form 25 as above and then the i-mpressionis taken of prepared tooth '15. To remove the impression and the investment form 25 a bail 30 is snapped in position, the spread ends 31 engaging the recess under the curved lip 26. The dentist now takes the fulcrum lift and proceeds as above having .bail 30 engage and seat in grove means 20 then lifting the investment form 25 to position B.

Having thus described our invention with particularity and detail, it will be readily apparent to those skilled in the art that many modifications may be made to the particular embodiment shown and described and it is to be understood that we do not wish to be limited to the precise details of construction as set forth, but desire to avail ourselves of all changes without departing from the spirit thereofor from the scope of the appended claims.

We claim:

'1. Apparatus for engaging a bail of an impression-form used on a prepared tooth and lifting the form by the bail so as to move the form in respect to said tooth, said lifting apparatus comprising; (1) a hinged upper jaw member having the portion from the hinge to the distal end formed with a diminishing extent, (2) a hinged lower jaw member having the portion from the hinge to the distal end formed witha diminishing extent, (3) means for maintaining the upper and lower jaw members in movable relationship to each other, (4) means for moving each jaw in relationship to each other, (5) at least one bail-retaining groove formed on the outward surface of the upper jaw and providing means for engaging and retaining a ball of an impression form, and (6) a support portion formed from the diminished distal end and extending downwardly from the lower jaw member, this support portion providing means for resting the apparatus on a tooth adjacent the prepared tooth While the bail is 4 urged upwardly by the bail-engaged upper jaw as the upper and lower ja-ws are manipulated so as to move away from each other.

' ing; (1) an upper jaw member, one end thereof being a relatively straight extended portion diminishing from the center to the distal end, the other end being a formed handle portion, ('2) a lower jaw member having a general shape diminishing from the center to the distal end, said distal end being bent at substantially right angles to the adjacent intermediate portion of the lower jaw member, said end providing a means for resting the apparatus on a tooth adjacent the prepared tooth, the other end of the lower member being a formed handle portion, (3) pivot means for retaining the upper and lower jaw members in movable relationship to each other and arranged so that as the handle portions of the upper and lower members are grasped and moved toward each other, the other end of the jaws will move away from each other, (4) at least one bail-retaining groove formed on the outward surface on the upper jaw, said groove providing for the engagement and retention of a bail of an impression form while the lower jaw is rested on the adjacent tooth and the upper jaw is urged upwardly to move the bail and form in respect to the prepared tooth.

References Cited by the Examiner OTHER REFERENCES Hospital Supply Catalog, 1942, A. S. Aloe Co., St. Louis, Mo., p. 567.

RICHARDA. GAUDET, Primary Examiner. ROBERT E. MORGAN, Examiner. 

1. APPARATUS FOR ENGAGING A BAIL OF AN IMPRESSION FORM USED ON A PREPARED TOOTH AND LIFTING THE FORM BY THE BAIL SO AS TO MOVE THE FORM IN RESPECT TO SAID TOOTH, SAID LIFTING APPARATUS COMPRISING; (1) A HINGED UPPER JAW MEMBER HAVING THE PORTION FROM THE HINGE TO THE DISTA END FORMED WITH A DIMINISHING EXTENT, (2) A HINGED LOWER JAW MEMBER HAVING THE PORTION FROM THE HINGE TO THE DISTAL END FORMED WITH A DIMINISHING EXTENT, (3) MEANS FOR MAINTING THE UPPER AND LOWER JAW MEMBERS IN MOVABLE RELATIONSHIP TO EACH OTHER, (4) MEANS FOR MOVING EACH JAW IN RELATIONSHIP TO EACH OTHER, (5) AT LEAST ONE BAIL-RETAINING GROOVE FORMED ON THE OUTWARD SURFACE OF THE UPPER JAW AND PROVIDING MEANS FOR ENGAGING AND RETAINING A BAIL OF AN IMPRESSION FORM, AND (6) A SUPPORT PORTION FORMED FROM THE DIMINISHED DISTAL END AND EXTENDING DOWNWARDLY FROM THE LOWER JAW MEMBER, THIS SUPPORT PORTION PROVIDING MEANS FOR RESTING THE APPARATUS ON A TOOTH ADJACENT THE PREPARED TOOTH WHILE THE BAIL IS URGED UPWARDLY BY THE BAIL-ENGAGED UPPER JAW AS THE UPPER AND LOWER JAWS ARE MANIPULATED SO AS TO MOVE AWAY FROM EACH OTHER. 